1. Field of the Invention
This invention relates to sensor apparatus.
More particularly the invention relates to sensor apparatus suitable for use in a system for detecting sludge in a tank, particularly storage tanks for oil or oil tanker ballast.
2. Description of Related Art
A sensor apparatus for such an application is often required to operate in a hazardous environment so that it is necessary that electrical components of the sensor be isolated from the environment without impairing the performance of the sensor.